The greatest barrier to effective communication is Poor Listening Skills: People not listening or not being present to the what's being said.
If both parties are listening poorly or not listening, miscommunication is likely to occur. People are likely to misunderstand each other, get defensive, and take actions or come to conclusions based on wrong information.
Have you ever witnessed or been in a conversation where the two people carry on, only to discover after a couple of minutes that they were talking about two completely different matters?
Or that they were arguing fiercely while both of them were pushing the same argument, just using different wording?
If at least one of the parties is listening, there is hope.
You can still have the beginnings of communication, because the person listening brings focus to the conversation. You can’t listen effectively unless you are paying attention to what’s being said.
Even when other barriers to effective communication are present, when one person starts really listening, the barriers begin to crumble.
No need to wait for others to start listening, start listening yourself and observe how others relax and start listening to you once they’ve feel they’ve been heard.
People may get distracted by internal or external factors. People may misinterpret what others say. People may be too attached to their personal point of view. You can read more about the The Causes of People Not Listening here.
Overcoming this barrier to effective communication requires focused effort, but it can be done.
You may start by reading (or re-reading) Stephen’s Covey “The 7 Habits of Highly Successful People”, paying special attention to Habit 5 “Seek first to understand, then to be understood."
You can practice the the listening exercises in this site which include Paraphrasing, Reflective Listening and Mindfulness exercises. This will go a long way to help you improve your listening skills.
You can then witness the magic of truly connecting with other people.
Read about other Communication Barriers